Electronic pen

Abstract

To provide an electronic pen that prevents a core body from rotating about an axis and allows a user to use the electronic pen without feeling discomfort when writing for input.SOLUTION: An electronic pen includes an enclosure 23, a core body portion including a core body 24 and a pressure member 14, a writing pressure detection unit 25X, and a holding member 13. The pressure member 14 holds a rear end of the core body 24 and presses the writing pressure detection unit 25X in accordance with a writing pressure applied to the core body 24. The holding member 13 is fixed in the enclosure 23 and formed in a tubular shape to store and hold the rear end side of the core body portion. At least a part of a side surface of the core body portion includes a flat surface portion parallel to an axial direction. The holding member 13 includes a protruding portion formed on at least a part of the inner wall surface. When the core body portion is mounted in the enclosure 23, the flat surface portion of the core body portion faces the protruding portion of the holding member 13.SELECTED DRAWING: Figure 3

Description

[[Technical Field]]

[0001] The present invention relates to an electronic pen used, for example, as a position indicator for a position detection device mounted in an information processing apparatus such as a tablet PC (Personal Computer). [[Background Art]]

[0002] Patent Document 1 described later discloses a configuration example of an electromagnetic induction type electronic pen 2. Specifically, as shown in FIG. 9(A), the electronic pen 2 is configured by mounting various members for realizing an electronic pen function in a housing 23. A core body 24 is inserted into a through hole of a ferrite core 22 so as to penetrate the ferrite core 22 in the axial direction. The portion of the core body 24 inserted into the through hole of the ferrite core 22 has a diameter slightly shorter than the diameter of the through hole, and is configured to be slidable in the axial direction within the through hole.

[0003] As shown in FIG. 9(A), a portion of the ferrite core 22 having a predetermined length including the center in the axial direction serves as a coil wound portion around which a coil 21 is wound along the axial direction, and portions on both sides of the coil wound portion serve as non-coil-wound portions around which no coil is wound. Conductive wires 21a and 21b, which are extension wires from both ends of the coil 21 wound around the ferrite core 22, extend inside the housing 23 to a printed circuit board 26, and are connected to a capacitor Cf provided on the printed circuit board 26. Accordingly, the coil 21 and the capacitor Cf on the printed circuit board 26 form a resonance circuit, which can mutually transmit and receive signals via electromagnetic induction with an electromagnetic induction type position detection device.

[0004] On the side of the core body 24 opposite the pen tip, a connection section 25 is provided, consisting of a molded section 25A, a pressure detection section 25B, a mating section 25C, and a connection terminal section 25D. The connection section 25 integrally connects the pen tip side, which consists of the coil 21, the ferrite core 22, and the core body 24, to the printed circuit board 26 and the circuit board protection pipe 27. Inside the molded section 25A, as shown in Figure 9(A), a core body holding section A1, conductive rubber A2, a ring spacer A3, a dielectric A4, and a terminal member A5 are provided. These parts are sandwiched between the molded section 25A and the mating section 25C to form a pressure detection section 25B, which is configured as a variable capacitance capacitor for detecting pen pressure.

[0005] The conductive wire connected to the conductive rubber A2 and the conductive wire connected to the terminal member A5 pass, for example, outside the molded portion 25A and the mating portion 25C, and are connected to the terminals of the connection terminal portion 25D, and through the terminals of the connection terminal portion 25D, they are connected to the electronic circuit of the printed circuit board 26. As a result, the pressure applied to the core body 24 can be detected in the electronic circuit portion of the printed circuit board 26 as a change in capacitance in the pressure detection unit 25B, which is configured as a variable capacitance capacitor, as described above.

[0006] The mating portion 25C is the part that mates with the substrate protection pipe 27. The mating portion 25C is formed, for example, in a roughly cylindrical shape from resin or hard rubber, and is firmly mated with the molded portion 25A to form a single unit. The inside of the mating portion 25C is provided with a recess into which the tip of the printed circuit board 26 is mated. When the substrate protection pipe 27 is mated with the mating portion 25C, the outer circumference of the substrate protection pipe 27 is aligned with the outer circumference of the mating portion 25C and the molded portion 25A.

[0007] As shown in Figure 9(A), the connection terminal section 25D is a part consisting of two plates, one above the other, that connect to the mating section 25C. These plates are designed to sandwich the printed circuit board 26, which will be described later. On one of these two plates, for example, the upper plate in Figure 9(A), a terminal is provided to which the conductive rubber A2 and the conductive wire from the terminal member A5 are connected, extending from the upper surface, wrapping around the end face on the circuit board side, to the lower surface. This ensures that when the printed circuit board 26 is inserted into the connection terminal section 25D, it is automatically connected to the terminals of the electronic circuits provided on the printed circuit board 26.

[0008] The printed circuit board 26 is formed by mounting terminals for the aforementioned electronic circuit and various circuit components that constitute the electronic circuit on a rectangular insulating substrate, and providing wiring to connect them. The various circuit components include an IC (Integrated Circuit) that functions as a control circuit, and multiple capacitors such as capacitor Cf. As shown in Figure 9(A), the printed circuit board 26 is housed and protected inside the substrate protection pipe 27.

[0009] The substrate protection pipe 27 is a rigid tubular member that is resistant to breakage and bending. The substrate protection pipe 27 has a core-side opening and a rear-end-side opening at both ends. The fitting portion 25C of the connecting portion 25 is inserted into a predetermined range on the inside of the substrate protection pipe 27 from the core-side opening, and the two are fitted together. Similarly, the pipe cover 28 is inserted into a predetermined range on the inside of the substrate protection pipe 27 from the rear-end-side opening, and the two are fitted together. This pipe cover 28 also has a recess into which the end of the printed circuit board 26 is inserted.

[0010] As a result, the core 24 is inserted from its rear end through the opening 23a of the housing 23, inserted into the core holding part A1, and mounted inside the housing 23 with its tip portion protruding from the housing 23. In other words, the core holding part A1 constitutes the mounting part for the core 24. In this case, the pen tip portion in which the core 24 is inserted through the ferrite core 22 around which the coil 21 is wound, the connection part 25, the circuit board protection pipe 27 housing the printed circuit board 26, and the pipe cover 28 are integrally connected. These are housed inside the housing 23 and held inside the housing 23 by being closed by the rear end cover 29, thus forming the electronic pen 2.

[0011] The equivalent circuit of the electronic pen 2 shown in Figure 9(A) is shown in Figure 9(B). Specifically, the coil 21, the pressure detection unit 25B which is configured as a variable capacitance capacitor, and the capacitor Cf on the printed circuit board 26 are connected in parallel to form a resonant circuit. This allows for the transmission and reception of signals with a position detection device equipped with an electromagnetic induction type position detection sensor, which will be described later. [Prior art documents] [Patent Documents]

[0012] [Patent Document 1] Japanese Patent Publication No. 2017-228185 [Overview of the Initiative] [Problems that the invention aims to solve]

[0013] In the case of the electromagnetic induction type electronic pen 2 shown in Figure 9, the core body 24 is made capable of sliding in the axial direction in response to the applied writing pressure. This allows the writing pressure applied to the core body 24 to be detected by the writing pressure detection unit 25B. For this reason, as can be seen in Figure 9(A), in order to avoid hindering the transmission of writing pressure, the sides of the core body 24 and the core body holder A1 are configured so that they do not come into contact with the inner wall surface of the surrounding ferrite core 22 or the inner wall surface of the molded part 25A. Due to this configuration, when writing input is performed by bringing the pen tip of the core body 24 of the electronic pen 2 into contact with the operating surface, the core body 24 and the core body holder A1 may rotate around the axis.

[0014] Existing writing instruments such as pencils, mechanical pencils, ballpoint pens, and fountain pens do not rotate around the axis of the pen tip when writing with the pen tip in contact with the paper. Therefore, when using the electronic pen 2, if the lead body 24 and the lead body holder A1 rotate around the axis, it gives the user an unprecedented writing sensation, which some users may find difficult to write with. This is not limited to electromagnetic induction electronic pens, but also applies to various types of electronic pens that have a configuration in which the lead body rotates around the axis.

[0015] In view of the above, this invention relates to an electronic pen and aims to prevent the core from rotating around its axis, thereby enabling the user to use it without feeling any discomfort during writing input. [Means for solving the problem]

[0016] To solve the above problems, A cylindrical housing having an opening at one end, A rod-shaped core is mounted inside the housing, with one end protruding from the opening of the housing as a pen tip, A pressure detection unit fixed within the housing detects the pressure applied to the core, A pressing member holds the rear end of the core inserted through the opening of the housing and presses the pressure detection unit in accordance with the pressure applied to the core, A cylindrical holding member fixed inside the housing houses and holds the pressing member. Equipped with, The pressing member is substantially cylindrical in shape and consists of a front portion and a rear portion that has a larger diameter than the front portion. The front end surface of the front portion is provided with a core-holding hole into which the rear end of the core is inserted. The holding member comprises a front fitting portion into which the front portion of the pressing member fits, and a rear fitting portion into which the rear portion of the pressing member fits. The pen tip end of the front fitting portion is provided with an insertion hole into which the core is inserted, and the rear end end of the rear fitting portion is provided with a rear end opening into which the pressing member is inserted. The inner wall surface of the front fitting portion of the retaining member and the side surface of the front portion of the pressing member do not have interlocking grooves or protrusions. The inner edge shape of the front fitting portion of the retaining member and the outer edge shape of the front portion of the pressing member allow the front portion of the pressing member to fit into the front fitting portion of the retaining member. However, rotation of the front portion of the pressing member around its axis is suppressed within the front fitting portion of the retaining member, and the inner wall surface of the front fitting portion of the retaining member and the side surface of the front portion of the pressing member are partially in contact. There is provided an electronic pen characterized by the above. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] [Figure 1] It is a diagram for explaining the configuration of the nib side portion of the electronic pen according to the embodiment. [Figure 2] It is a diagram for explaining a holding member and a pressing member of the electronic pen according to the embodiment. [Figure 3] It is a diagram for explaining a state where a front side portion of the pressing member is fitted into a front side fitting portion of the holding member of the electronic pen according to the embodiment. [Figure 4] It is a diagram for explaining another example of the holding member. [Figure 5] It is a diagram for explaining another example of the holding member. [Figure 6] It is a diagram for explaining another example of the holding member. [Figure 7] It is a diagram for explaining another example of the holding member. [Figure 8] It is a diagram for explaining another example of the pressing member. [Figure 9] It is a diagram for explaining a configuration example of a conventional electronic pen. DESCRIPTION OF EMBODIMENTS

[0020] Hereinafter, embodiments of the electronic pen according to the present invention will be described with reference to the drawings. There are various detection methods for a designated position used between an electronic pen and a position detection device. The present invention is applicable to various types of electronic pens, and can be applied to, for example, an electromagnetic induction type electronic pen and a capacitive type electronic pen.

[0021] The electromagnetic induction method includes a position detection device equipped with a sensor unit having multiple loop coils arranged in both the X-axis and Y-axis directions. The device alternates between a transmission period, during which power is sequentially supplied to the multiple loop coils in the sensor unit to generate a magnetic field, and a reception period, during which power is stopped to receive an external magnetic field. The corresponding electronic pen includes a resonant circuit consisting of a coil and a capacitor. In response to the magnetic field from the sensor unit, current flows through the coil, generating a signal, and this signal includes pen pressure information. Position detection device The data is transmitted to the position detection device during the reception period, and the position and pressure indicated by the electronic pen are detected.

[0022] On the other hand, the capacitive method includes a position detection device equipped with a sensor unit that has multiple linear conductors (line electrodes) arranged in both the X-axis and Y-axis directions. This sensor unit detects the indicated position in response to changes in capacitance (charge) generated in the linear conductors when a finger or electrostatic pen is brought close to it. Electrostatic pens include a conductive pen-type position indicator and an electronic pen using an active electrostatic coupling method (AES (Active Electrostatic) method) that is battery-powered and transmits signals. Electronic pens using the active electrostatic coupling method are sometimes called active electrostatic pens or AES pens. In the case of the active electrostatic coupling method using an active electrostatic pen, the electronic pen transmits a signal from an oscillator circuit mounted on the electronic pen, including pen pressure information, which is received by the position detection device to detect the indicated position and pen pressure. In the following explanation, for the sake of simplicity, this invention will be described using the case where it is applied to an electronic pen using an electromagnetic induction method (EMR (Electro Magnetic Resonance) method) as an example.

[0023] [Example of the main components of electronic pen 1] Figure 1 is a diagram illustrating an example of the configuration of the pen tip portion of the electronic pen 1 of this embodiment. As mentioned above, the electronic pen 1 of this embodiment uses an electromagnetic induction method, and its basic configuration is the same as that of the conventional electromagnetic induction electronic pen 2 shown in Figure 9. For this reason, in Figure 1, the same reference numerals are used for parts that are configured in the same way as the conventional electromagnetic induction electronic pen 2 shown in Figure 9(A), and a detailed explanation of these parts will be omitted to avoid redundancy. However, the electronic pen 1 of this embodiment has some differences in the configuration of the pen tip portion compared to the conventional electronic pen 2. In the following, the electronic pen 1 of this embodiment will be described focusing on the parts that differ from the conventional electronic pen 2 shown in Figure 9.

[0024] In the case of the electronic pen 1 of this embodiment, the ferrite core 22, on which the coil 21 is wound around its side, is held by a tip holding portion 11 and a rear end holding portion 12. The tip holding portion 11 is provided in contact with the inner wall surface on the pen tip side of the housing 23 and holds the tip end of the ferrite core 22 on the pen tip side. The rear end holding portion 12 is provided by fitting a part of its rear end into a fitting hole provided on the pen tip side of a holding member 13, which will be described later, and holds the rear end of the ferrite core 22. As a result, the position of the ferrite core 22 within the housing 23 is always restricted, and the ferrite core 22 is held stably so that it does not rattle.

[0025] Furthermore, in the case of the electronic pen 1 of this embodiment, the core body 24 has a configuration consisting of a pen tip portion 24a and a shaft portion 24b. The pen tip portion 24a is formed in a dome shape from a resin material such as polyacetal, and the shaft portion 24b is formed in a rod shape from a carbon material, for example. Within the pen tip portion, the space between the pen tip portion 24a and the shaft portion 24b is made of a different resin than that of the pen tip portion 24a. For example, it is a resin that is harder than that of the pen tip portion 24a. As a result, the core body 24 is slender and has the characteristics of not scratching the operating surface of electronic devices, having a good writing feel, less wear on the pen tip, and the shaft portion 24b being less likely to break.

[0026] Furthermore, the electronic pen 1 of this embodiment includes a configuration in which a pressing member 14, which holds the rear end of the core body 24 and presses the pressure detection unit 25X in accordance with the writing pressure applied to the core body 24, is housed and held within the holding member 13. In this embodiment, as will be described in detail later, a configuration is achieved in which the pressing member 14 does not rotate about its axis within the holding member 13. This prevents the core body 24, whose rear end is held by the pressing member 14, from rotating about its axis.

[0027] In the conventional electronic pen 2 shown in Figure 9(A), the pressure detection unit 25B was described as consisting of a core holder A1, conductive rubber A2, ring spacer A3, dielectric A4, and terminal member A5. However, in the case of the electronic pen 1 of this embodiment, the pressing member 14 corresponding to the core holder A1 and the newly provided holding member 13 are distinctive features. On the other hand, the part consisting of conductive rubber A2, ring spacer A3, dielectric A4, and terminal member A5 is configured in the same way as the conventional electronic pen 2. Therefore, in the electronic pen 1 of this embodiment, the part consisting of conductive rubber A2, ring spacer A3, dielectric A4, and terminal member A5, excluding the pressing member 14 corresponding to the core holder A1, is designated as the pressure detection unit 25X.

[0028] As shown in Figure 1, the retaining member 13 is a cylindrical object fixed inside the housing 23 by a fitting portion 25C so as not to move in the axial direction or rotate about the axis, and houses and holds a substantially cylindrical pressing member 14. As shown in Figure 1, the retaining member 13 includes a front fitting portion 13F into which the front part of the pressing member 14 (described in more detail later) fits, and a rear fitting portion 13Bk into which the rear part of the pressing member 14 fits. In this case, the diameter of the rear fitting portion 13Bk is longer than the diameter of the front fitting portion 13F. Furthermore, the tip end of the front fitting portion 13F is provided with a core insertion hole through which the core 24 is inserted, and the rear end of the rear fitting portion 13Bk is provided with a rear end opening for loading the pressing member 14.

[0029] On the other hand, as shown in Figure 1, the pressing member 14 is housed and held within the holding member 13. The pressing member 14 holds the rear end of the core body 24 inserted from the pen tip side opening 23a of the housing 23 and functions to press the pressure detection unit 25X in accordance with the writing pressure applied to the pen tip of the core body 24. The pressing member 14, as will be described in more detail later, is roughly cylindrical in shape and consists of a front part that fits into the front fitting part 13F of the holding member 13 and a rear part that fits into the rear fitting part 13Bk of the holding member 13. Furthermore, as shown in Figure 1, the pressing member 14 is provided with a core body holding hole from the front end surface of the front part into which the rear end of the core body 24 is inserted, and it holds the rear end of the core body 24 inserted from the core body holding hole. Furthermore, as shown in Figure 1, the rear end surface of the rear portion of the pressing member 14 is formed in a spherical shape to press against the conductive rubber A2 of the pen pressure detection unit 25X.

[0030] [Example configuration of the holding member 13 and the pressing member 14] The configurations of the holding member 13 and the pressing member 14 will be described in detail below. Figure 2 is a diagram illustrating the holding member 13 and the pressing member 14 of the electronic pen 1 according to this embodiment. In Figure 2, Figure 2(A) is a view of the holding member 13 from the rear end, and Figure 2(B) is a perspective view of the pressing member 14.

[0031] As shown in Figure 1, the retaining member 13 is cylindrical, but its tip end is a wider portion 13S that extends outward from the cylindrical portion. As shown in Figure 2(A), this wider portion 13S consists of a portion with opposing arc-shaped sides and a portion with opposing straight sides. In this case, the straight side joins with the straight inner wall surface of the fitting portion 25C, preventing the retaining member 13 itself from rotating about its axis within the housing 23. Furthermore, the wider portion 13S is pushed from the rear end towards the tip side of the side wall of the fitting portion 25C by its end face, thereby preventing the retaining member 13 from moving in the axial direction within the housing 23. The wider portion 13S on the tip side of the retaining member 13 also engages with a projection (not shown) provided on the inner wall surface of the housing 23 at the tip side, preventing it from moving towards the tip.

[0032] Furthermore, as shown in Figure 2(A), when viewed from the rear end, the retaining member 13 has a rear end opening 13H at the rear end and a lead insertion hole 13L at the pen tip end. Also, as shown in Figure 1, the inside of the retaining member 13 has a front fitting portion 13F on the pen tip side and a rear fitting portion 13Bk with a larger diameter than the front fitting portion 13F at its rear end. The rear fitting portion 13Bk is a cylindrical space.

[0033] In contrast, the front fitting portion 13F is not a cylindrical space, but rather has mountain-shaped surfaces 13a and 13b formed on its inner wall surface at positions opposite each other, with the core insertion hole 13L in between. The mountain-shaped surfaces 13a and 13b of the front fitting portion 13F are formed in a mountain shape (V-shape) with the linear portion as the apex and surfaces inclined to the left and right, as shown in Figure 2(A), by having a single linear portion extending in the direction along the axial center protrude inward. The portion of the front fitting portion 13F that is not the mountain-shaped surfaces 13a and 13b is an arc-shaped inner wall surface.

[0034] As described above, the pressing member 14 is inserted into and held within the holding member 13 through the rear end opening 13H of the holding member 13. As shown in Figure 2(B), the pressing member 14 is substantially cylindrical in shape and consists of a front part 14F and a rear part 14Bk. As shown in Figure 2(B), a core holding hole 14L is provided on the front end surface of the front part 14F. The rear end of the core 24 is inserted into the pressing member 14 through the core holding hole 14L and is held in contact with the portion that protrudes from the inner bottom surface toward the pen tip, as shown in Figure 1. As a result, when writing pressure is applied to the core 24, the conductive rubber A2 of the writing pressure detection unit 25X can be pressed by the rear end surface of the pressing member 14 in which the core 24 is held, over a wider area than the rear end surface of the core 24 itself.

[0035] The front portion 14F of the pressing member is the part that fits into the front fitting portion 13F of the holding member 13. As shown in Figure 2(B), each of the pair of sides facing each other across the core holding hole 14L is a smooth, flat surface (pressing member flat portion) 14a, 14b. In addition, each of the pair of sides of the front portion 14F that are not flat portions 14a, 14b is arc-shaped. As will be described in more detail later, the flat portions 14a, 14b are the parts that face the mountain-shaped surfaces 13a, 13b of the front fitting portion 13F of the holding member 13, and the arc-shaped side portions are the parts that face the arc-shaped inner wall surface portion of the holding member 13.

[0036] In the front portion 14F, the distance (length) between the flat portion 14a and the flat portion 14b is slightly shorter than the straight-line distance (length) connecting the vertex of the mountain-shaped surface portion 13a and the vertex of the mountain-shaped surface portion 13b of the front fitting portion 13F of the retaining member 13. Also, the straight-line distance (inner diameter of the front portion 14F) passing through the center of the front portion 14F and connecting the arc-shaped side surfaces is slightly shorter than the straight-line distance (inner diameter of the front fitting portion 13F) passing through the center of the front fitting portion 13F of the retaining member 13 and connecting the arc-shaped inner wall surfaces. As a result, the front portion 14F of the pressing member 14 can be fitted into the front fitting portion 13F of the retaining member 13.

[0037] As shown in Figure 2(B), the rear portion 14Bk of the pressing member 14 consists of three parts: a front overhang 14x, an intermediate portion 14y, and a rear overhang 14z. As shown in Figure 2(B), the front overhang 14x and the rear overhang 14z are disc-shaped portions with a slight thickness in the axial direction, and the diameter (outer diameter) of these portions is slightly shorter than the inner diameter of the rear fitting portion 13Bk of the retaining member 13.

[0038] Furthermore, the intermediate portion 14y is the part that connects the front protruding portion 14x and the rear protruding portion 14z, and has a flat side surface, as well as a portion that is hollowed out in a direction intersecting the axis, forming a through hole in a direction intersecting the axis. This allows the rear portion 14Bk of the pressing member 14 to be fitted into the rear fitting portion 13Bk of the retaining member 13. In this case, the sides of the front protruding portion 14x and the rear protruding portion 14z may come into contact with the inner wall surface of the rear fitting portion 13Bk of the retaining member 13.

[0039] Thus, in this embodiment of the electronic pen 1, the pressing member 14 is inserted into the holding member 13 from the front part 14F through the rear end opening of the holding member 13. In this case, as shown in Figure 1, the front part 14F of the pressing member 14 fits into the front fitting part 13F of the holding member 13, and the rear part 14Bk of the pressing member 14 fits into the rear fitting part 13Bk of the holding member 13, so that the pressing member 14 is held inside the holding member 13.

[0040] Figure 3 is a diagram illustrating the state in which the front part 14F of the pressing member 14 is fitted into the front fitting part 13F of the holding member 13. Specifically, Figure 3(A) is a cross-sectional view from the pen tip side when the front fitting part 13F is cut in a direction intersecting the axis, with the pressing member 14 mounted and held inside the holding member 13. Figure 3(B) is a view of the same part from the direction indicated by the arrow in Figure 3(A), and is shown assuming that the front fitting part 13F of the holding member 13 is transparent.

[0041] The inner space of the front fitting portion 13F of the retaining member 13 (the space into which the front portion 14F of the pressing member 14 fits) is, as shown in Figure 3(A), a space in which the mountain-shaped surface portion 13a and the mountain-shaped surface portion 13b face each other, and the arc-shaped inner wall surface 13c and the arc-shaped inner wall surface 13d face each other. Assume that the front portion 14F of the pressing member 14 is fitted into this inner space of the front fitting portion 13F of the retaining member 13. In this case, as shown in Figure 3(A), the mountain-shaped surface portion 13a of the retaining member 13 faces the flat portion 14a of the pressing member 14, and the mountain-shaped surface portion 13b of the retaining member 13 faces the flat portion 14b of the pressing member 14. Furthermore, the arc-shaped inner wall surface 13c of the holding member 13 and the arc-shaped side surface 14c of the pressing member 14 face each other, and the arc-shaped inner wall surface 13d of the holding member 13 and the arc-shaped side surface 14d of the pressing member 14 face each other.

[0042] As can be seen in Figure 3(A), the opening shape in the direction intersecting the axis of the inner space of the front fitting portion 13F of the retaining member 13 is not circular, and the cross-sectional shape when the front portion 14F of the pressing member 14 is cut in the direction intersecting the axis is also not circular. Furthermore, although the diameter of the arc-shaped inner wall portion of the retaining member 13 and the diameter of the arc-shaped side portion of the pressing member 14 are similar, the latter is shorter than the former. Therefore, the pressing member 14 can move (slide) in the axial direction within the retaining member 13, but the front portion 14F of the pressing member 14 cannot rotate within the inner space of the front fitting portion 13F of the retaining member 13.

[0043] In other words, as shown in Figure 3(A), suppose a force is applied to the core body 24 that causes it to rotate around its axis when the pressing member 14 is holding the rear end of the core body 24. In this case, the flat portions 14a and 14b on the front side of the pressing member 14 come into contact with the mountain-shaped portions 13a and 13b of the front fitting portion 13F of the holding member 13, preventing the pressing member 14 from rotating within the holding member 13. Therefore, the core body 24 held by the pressing member 14 also does not rotate around its axis. This prevents the core body 24 from rotating around its axis.

[0044] Furthermore, where the mountain-shaped surface 13a of the holding member 13 and the flat surface 14a of the pressing member 14 face each other, the opposing surfaces (slope and flat surface) make large contact. As a result, even if the pressing member 14 rotates slightly, the flat surface and the mountain-shaped surface remain in surface-to-surface contact, preventing the pressing member 14 from getting caught and fixed inside the holding member 13. As shown in Figure 3(B), the flat surface 14a of the pressing member 14 mainly comes into contact with the apex Pa portion of the mountain-shaped surface 13a, as indicated by the dotted line, but it does not get caught and fixed. Similarly, where the mountain-shaped surface 13b of the holding member 13 and the flat surface 14b of the pressing member 14 face each other, the area of ​​contact between the opposing surfaces becomes larger.

[0045] In this case as well, similar to the case shown in Figure 3(B), the apex Pb portion of the mountain-shaped surface portion 13b mainly comes into contact with the flat portion 14b of the pressing member 14, but it does not get caught and fixed. In other words, even if a force is applied that causes the core body 24 and the pressing member 14 to rotate around the axis, it is prevented that the inner wall surface of the holding member 13 and the side surface of the pressing member 14 become firmly engaged, and the contact (engagement) is limited to soft contact between the surfaces.

[0046] Therefore, the contact area between the side surface of the front portion 14F of the pressing member 14 and the inner wall surface of the front fitting portion 13F of the holding member 13 can be increased. This prevents snagging between the inner wall surface of the front fitting portion 13F of the holding member 13 and the side surface of the front portion 14F of the pressing member 14, and the axial movement of the core body 24 and the pressing member 14 is not hindered. In other words, the writing pressure applied to the core body 24 can be appropriately transmitted to the writing pressure detection unit 25X.

[0047] [Effects of the embodiment] As described above, in the electronic pen 1 of this embodiment, it is possible to prevent the front part 14F of the pressing member 14 from rotating about its axis within the front fitting part 13F of the holding member 13. This also prevents the core body 24, whose rear end is held by the pressing member 14, from rotating about its axis. In this case, the inner edge shape of the front fitting part 13F of the holding member 13 and the outer edge shape of the front part 14F of the pressing member 14 are not similar circles. Also, the size of the inner edge of the front fitting part 13F of the holding member 13 is not large enough for the front part 14F of the pressing member 14 to rotate. In other words, the shape and size of the inner edge of the front fitting part 13F of the holding member 13 and the shape and size of the outer edge of the front part 14F of the pressing member 14 are similar. Therefore, although the two can be fitted together, it is possible to prevent the front part 14F of the pressing member 14 from rotating about its axis within the inner space of the front fitting part 13F of the holding member 13.

[0048] Furthermore, as explained using Figure 3(A), the inner wall surface of the front fitting portion 13F of the holding member 13 is provided with opposing mountain-shaped surfaces 13a and 13b, while the side surfaces of the front portion 14F of the pressing member 14, which face these mountain-shaped surfaces 13a and 13b, are flat surfaces 14a and 14b. With this configuration, the contact area between the inner wall surface of the front fitting portion 13F of the holding member 13 and the side surfaces of the front portion 14F of the pressing member 14 is slightly reduced, but since they are in contact surface to surface, smooth movement is possible without causing snagging when the core body 24 and the pressing member 14 move in the axial direction. As a result, a rotation prevention mechanism around the axis of the core body 24 and the pressing member 14 can be realized without interfering with pen pressure detection.

[0049] Therefore, in the case of the electronic pen 1 described above, there is no need to provide interlocking grooves on the inner wall surface (inner side surface) of the front fitting portion 13F of the holding member 13 and the side surface (outer side surface) of the front portion 14F of the pressing member 14 in order to prevent rotation of the core body 24 and the pressing member 14. Therefore, loading the pressing member 14 into the holding member 13 does not become difficult, and loading using an automatic assembly machine is also possible. In other words, by eliminating the mechanism to prevent rotation of the core body 24, the assembly of the electronic pen does not become difficult, and assembly using an automatic assembly machine is also possible.

[0050] [Differentiation] In the embodiment described above, the inner wall surface of the holding member 13 is provided with mountain-shaped surfaces 13a and 13b, and the opposing surfaces of the pressing member 14 are flat surfaces 14a and 14b, but the embodiment is not limited to this. Various deformations are possible for the mountain-shaped surfaces 13a and 13b, and various deformations are also possible for the flat surfaces 14a and 14b. Below, we will describe modified examples of the mountain-shaped surfaces 13a and 13b of the holding member 13, modified examples of the flat surfaces 14a and 14b of the pressing member 14, and modified examples of the appearance of the pressing member 14. In the modified examples described below, the configuration other than the parts shown as modified examples is the same as in the case of the electronic pen 1 described using Figures 1 to 3. Therefore, in the modified examples described below, the explanation of the parts that are the same as in the case of the electronic pen 1 described using Figures 1 to 3 will be redundant and will be omitted.

[0051] <Modification 1: The mountain-shaped surface of the retaining member has two vertices> Figure 4 is a diagram illustrating another example (modification 1) of the retaining member 13, and illustrates the state in which the front part 14F of the pressing member 14 is fitted into the front fitting part 13FA of the retaining member 13A. Specifically, Figure 4(A) is a cross-sectional view taken from the pen tip side when the front fitting part 13FA is cut in a direction intersecting the axis, with the pressing member 14 mounted and held inside the retaining member 13A. Figure 4(B) is a view of the same part from the direction indicated by the arrow in Figure 4(A), and is shown assuming that the front fitting part 13FA of the retaining member 13A is transparent.

[0052] In this example, the retaining member 13A differs from the retaining member 13 in the embodiment described above in the configuration of the inner wall surface of the front fitting portion 13FA, but the other components are configured in the same way as the retaining member 13 in the embodiment described above. In the inner space of the front fitting portion 13FA of the retaining member 13A in this example (the space into which the front portion 14F of the pressing member 14 fits), as shown in Figure 4(A), a mountain-shaped surface portion 13aA having two vertices Pc and Pd and a mountain-shaped surface portion 13bA having two vertices Pe and Pf face each other. Also, an outwardly bulging arc-shaped inner wall surface 13cA and an arc-shaped inner wall surface 13dA face each other.

[0053] Assume that the front part 14F of the pressing member 14 is fitted into the inner space of the front fitting part 13FA of the retaining member 13A. In this case, as shown in Figure 4(A), the mountain-shaped surface 13aA of the retaining member 13A and the flat surface 14a of the pressing member 14 face each other, and the mountain-shaped surface 13bA of the retaining member 13A and the flat surface 14b of the pressing member 14 face each other. Furthermore, the arc-shaped inner wall surface 13cA of the retaining member 13A and the arc-shaped side surface 14c of the pressing member 14 face each other, and the arc-shaped inner wall surface 13dA of the retaining member 13A and the arc-shaped side surface 14d of the pressing member 14 face each other.

[0054] As can be seen in Figure 4(A), the outer edge shape of the front portion 14F of the pressing member 14 is not circular, the inner edge shape of the front fitting portion 13FA of the retaining member 13A is not circular, and the gap between the two members is small. Therefore, the front portion 14F of the pressing member 14 cannot rotate about its axis within the inner space of the front fitting portion 13FA of the retaining member 13A.

[0055] Furthermore, as shown in Figure 4(B), the flat portion 14a of the pressing member 14 is mainly contacted by the two vertices Pc and Pd of the mountain-shaped surface 13aA, as indicated by the dotted line, and the opposing surfaces do not come into large contact with each other. Similarly, the flat portion 14b of the pressing member 14 is contacted by the two vertices Pe and Pf of the mountain-shaped surface 13bA, and although the opposing surfaces do not come into large contact with each other, it can be considered as surface-to-surface contact.

[0056] Therefore, although the contact area between the side surface of the front portion 14F of the pressing member 14 and the inner wall surface of the front fitting portion 13FA of the holding member 13A is slightly reduced, surface-to-surface contact is still possible. This prevents snagging between the inner wall surface of the front fitting portion 13FA of the holding member 13A and the side surface of the front portion 14F of the pressing member 14, and does not hinder the axial movement of the core body 24 and the pressing member 14. In other words, the writing pressure applied to the core body 24 can be appropriately transmitted to the writing pressure detection unit 25X.

[0057] In the modified example shown in Figure 4, the rotation of the pressing member 14 around its axis within the front fitting portion 13FA of the holding member 13A can be suppressed more effectively than in the case of the electronic pen 1 shown in Figure 3. Furthermore, the number of vertices on the mountain-shaped surface is not limited to one (Figure 3) or two (Figure 4). The number of vertices on the mountain-shaped surface may be three or more, but as the number of vertices increases, the likelihood of snagging between the inner wall surface of the front fitting portion of the holding member and the side surface of the front portion of the pressing member increases, so it is necessary to keep the number of vertices to a level that prevents snagging.

[0058] <Modification 2: Replace the mountain-shaped surface with an arc-shaped surface that bulges inward in an arc shape.> Figure 5 is a diagram illustrating another example (modification 2) of the retaining member 13, and illustrates the state in which the front part 14F of the pressing member 14 is fitted into the front fitting part 13FC of the retaining member 13C. Specifically, Figure 5(A) is a cross-sectional view from the pen tip side when the front fitting part 13FC is cut in a direction intersecting the axis, with the pressing member 14 mounted and held inside the retaining member 13C. Figure 5(B) is a view of the same part from the direction indicated by the arrow in Figure 5(A), and is shown assuming that the front fitting part 13FC of the retaining member 13C is transparent.

[0059] In this example, the retaining member 13C differs from the retaining member 13 in the embodiment described above in the configuration of the inner wall surface of the front fitting portion 13FC, but the other components are configured in the same way as the retaining member 13 in the embodiment described above. In the inner space of the front fitting portion 13FC of the retaining member 13C in this example (the space into which the front portion 14F of the pressing member 14 fits), as shown in Figure 5(A), an arc-shaped surface portion 13aC and a similar arc-shaped surface portion 13bC face each other. The arc-shaped surfaces 13aC and 13bC bulge inward in an arc shape, resembling the top surface of a rolled cake. In addition, an arc-shaped inner wall surface 13cC and an arc-shaped inner wall surface 13dC that bulge outward face each other.

[0060] Assume that the front part 14F of the pressing member 14 is fitted into the inner space of the front fitting part 13FC of the retaining member 13C. In this case, as shown in Figure 5(A), the arc-shaped surface part 13aC of the retaining member 13C and the flat part 14a of the pressing member 14 face each other, and the arc-shaped surface part 13bC of the retaining member 13C and the flat part 14b of the pressing member 14 face each other. Furthermore, the arc-shaped inner wall surface 13cC of the retaining member 13C and the arc-shaped side surface 14c of the pressing member 14 face each other, and the arc-shaped inner wall surface 13dC of the retaining member 13C and the arc-shaped side surface 14d of the pressing member 14 face each other.

[0061] As can be seen in Figure 5(A), the outer edge shape of the front portion 14F of the pressing member 14 is not circular, and the inner edge shape of the front fitting portion 13FC of the retaining member 13C is also not circular, and the gap between the two members is small. For this reason, the front portion 14F of the pressing member 14 cannot rotate about its axis within the inner space of the front fitting portion 13FA of the retaining member 13C.

[0062] Furthermore, as shown in Figure 5(B), the vertex portion SL of the arc-shaped surface portion 13aC mainly contacts the flat portion 14a of the pressing member 14, as indicated by the dotted line, and the opposing surfaces do not come into large contact with each other. Similarly, the vertex portion of the arc-shaped surface portion 13bC contacts the flat portion 14b of the pressing member 14, and although the opposing surfaces do not come into large contact with each other, in this case too, it can be considered that the surfaces are in contact with each other.

[0063] Therefore, although the contact area between the side surface of the front portion 14F of the pressing member 14 and the inner wall surface of the front fitting portion 13FC of the holding member 13C is slightly reduced, surface-to-surface contact is still possible. This prevents snagging between the inner wall surface of the front fitting portion 13FC of the holding member 13C and the side surface of the front portion 14F of the pressing member 14, and does not hinder the axial movement of the core body 24 and the pressing member 14. In other words, the writing pressure applied to the core body 24 can be appropriately transmitted to the writing pressure detection unit 25X.

[0064] In the modified example shown in Figure 5, if the radius of the upper part of the arc-shaped surface portions 13aC and 13bC is made too long, the inward bulge will become gentler, and the contact width with the flat portions 14a and 14b of the opposing pressing member 14 will widen. In this case, there is a higher possibility of snagging between the inner wall surface of the front fitting portion of the holding member and the side surface of the front portion of the pressing member. Therefore, the radius of the upper part of the arc-shaped surface portions 13aC and 13bC, that is, the degree of inward bulge, must be determined in a way that does not cause snagging.

[0065] <Modification 3: Replace the mountain-shaped surface with a spherical surface that bulges inward in a spherical (dome-shaped) form.> Figure 6 is a diagram illustrating another example (modification 3) of the retaining member 13, and illustrates the state in which the front part 14F of the pressing member 14 is fitted into the front fitting part 13FD of the retaining member 13D. Specifically, Figure 6(A) is a cross-sectional view from the pen tip side when the front fitting part 13FD is cut in a direction intersecting the axis, with the pressing member 14 mounted and held inside the retaining member 13D. Figure 6(B) is a view of the same part from the direction indicated by the arrow in Figure 6(A), and is shown assuming that the front fitting part 13FD of the retaining member 13D is transparent.

[0066] In this example, the retaining member 13D differs from the retaining member 13 in the embodiment described above in the configuration of the inner wall surface of the front fitting portion 13FD, but the other components are configured in the same way as the retaining member 13 in the embodiment described above. In the inner space of the front fitting portion 13FD of the retaining member 13D in this example (the space into which the front portion 14F of the pressing member 14 fits), as shown in Figure 6(A), a spherical portion 13aD that bulges inward in a dome shape, resembling a part of a ball, and a similar spherical portion 13bD face each other. Also, an arc-shaped inner wall surface 13cD that bulges outward and an arc-shaped inner wall surface 13dD face each other.

[0067] Assume that the front portion 14F of the pressing member 14 is fitted into the inner space of the front fitting portion 13FD of the retaining member 13D. In this case, as shown in Figure 6(A), the spherical portion 13aD of the retaining member 13D and the flat portion 14a of the pressing member 14 face each other, and the spherical portion 13bD of the retaining member 13D and the flat portion 14b of the pressing member 14 face each other. Furthermore, the arc-shaped inner wall surface 13cD of the retaining member 13D and the arc-shaped side surface 14c of the pressing member 14 face each other, and the arc-shaped inner wall surface 13dD of the retaining member 13D and the arc-shaped side surface 14d of the pressing member 14 face each other.

[0068] As can be seen in Figure 6(A), the outer edge shape of the front part 14F of the pressing member 14 is not circular, and the inner edge shape of the front fitting part 13FD of the retaining member 13D is also not circular, and the gap between the two members is small. For this reason, the front part 14F of the pressing member 14 is not circular. 13D Front fitting part 13FD Within its inner space, rotation around the axis is not possible.

[0069] Furthermore, as shown in Figure 6(B), the flat portion 14a of the pressing member 14 mainly comes into contact with the apex portion SP of the spherical portion 13aD, as indicated by the small dotted circle, and the opposing surfaces do not come into large contact with each other. Similarly, the flat portion 14b of the pressing member 14 comes into contact with the apex portion of the spherical portion 13bD, and the opposing surfaces do not come into large contact with each other.

[0070] However, although the contact area between the side surface of the front portion 14F of the pressing member 14 and the inner wall surface of the front fitting portion 13FD of the holding member 13D is slightly reduced, surface-to-surface contact is still possible. This prevents the inner wall surface of the front fitting portion 13FD of the holding member 13D and the side surface of the front portion 14F of the pressing member 14 from becoming firmly engaged, thus preventing so-called snagging, and ensuring that the axial movement of the core body 24 and the pressing member 14 is not hindered. In other words, the writing pressure applied to the core body 24 can be appropriately transmitted to the writing pressure detection unit 25X.

[0071] In the modified example shown in Figure 6, if the protrusion of the spherical portions 13aD and 13bD is made too large, the contact area with the flat portions 14a and 14b of the opposing pressing member 14 will increase. In this case, there is a higher possibility of snagging between the inner wall surface of the front fitting portion of the holding member and the side surface of the front portion of the pressing member. Therefore, the degree of protrusion of the spherical portions 13aD and 13bD must be determined in such a way that snagging does not occur.

[0072] <Modification 4: Changing the shape of the side surface of the pressing member> Figure 7 is a diagram illustrating another example (modification 4) of the retaining member 13 and the pressing member 14, and illustrates the state in which the front part 14FA of the pressing member 14A is fitted into the front fitting part 13FE of the retaining member 13E. Specifically, Figure 7(A) is a cross-sectional view taken from the pen tip side when the front fitting part 13FE is cut in a direction intersecting the axis, with the pressing member 14A mounted and held inside the retaining member 13E.

[0073] In this example, the retaining member 13E differs from the retaining member 13 in the above-described embodiment in the configuration of the inner wall surface of the front fitting portion 13FE, but the other components are configured in the same way as the retaining member 13 in the above-described embodiment. Similarly, in this example, the pressing member 14A differs from the pressing member 14 in the above-described embodiment in the configuration of the side surface of the front portion 14FA, but the other components are configured in the same way as the pressing member 14 in the above-described embodiment.

[0074] In this example, the inner space of the front fitting portion 13FE of the retaining member 13E (pressing member)14A Front part 14FA In the space where the two parts fit together, as shown in Figure 7(A), a smoothed flat portion (holding member flat portion) 13aE and a smoothed flat portion (holding member flat portion) 13bE face each other. Also, an arc-shaped inner wall surface 13cE and an arc-shaped inner wall surface 13dE face each other. On the other hand, the pressing member 14A has mountain-shaped surfaces 14aA and 14bA on the sides facing each other across the core holding hole 14L.

[0075] In other words, the mountain-shaped surfaces 14aA and 14bA of the front part 14FA of the pressing member are formed by a single linear portion extending in the direction along the axial direction, projecting outward (towards the inner wall surface of the holding member 13E). As a result, as shown in Figure 7(A), the mountain-shaped surfaces 14aA and 14bA are formed with the linear portions PC and PD as apex, and the surfaces are inclined to the left and right in a mountain shape (V-shape). The portion of the front part 14FA of the pressing member 14A that is not the mountain-shaped surfaces 14aA and 14bA has an arc-shaped side surface.

[0076] This creates a state where the relationship between the flat surface and the V-shaped surface of the front fitting portion 13F of the holding member 13 and the front portion 14F of the pressing member 14, as shown in Figure 3(A), is reversed. In this case, the front portion 14F of the pressing member 14 cannot rotate about its axis within the front fitting portion 13F of the holding member 13. That is, the state shown in Figure 7 is the same as the state shown in Figure 3(B), and the front portion of the pressing member 14A is mainly the front portion of the front fitting portion 13FE of the holding member 13E, as shown by the dotted line. 14FA mountain-shaped surface 14aA The vertex PC portion will come into contact with it. Similarly, the flat portion 13bE of the front fitting portion 13FE of the holding member 13E will mainly come into contact with the front portion of the pressing member 14A. 14FA mountain-shaped surface 14bA The vertex PD portion will come into contact with each other.

[0077] However, when a rotational force is applied to the core 24 and the pressing member 14A around the axis, the flat portion 13aE of the holding member 13E and the mountain-shaped portion 14aA of the pressing member 14A come into contact at the point where they face each other. Similarly, the flat portion 13bE of the holding member 13E and the mountain-shaped portion 14bA of the pressing member 14A come into contact at the point where they face each other. As a result, the inner wall surface of the holding member 13E and the side surface of the pressing member 14A become loosely engaged. Consequently, the inner wall surface of the holding member 13E and the side surface of the pressing member 14A do not strongly engage, preventing a so-called snagging condition, and thus enabling proper detection of pen pressure.

[0078] Therefore, similar to the case of the retaining member 13E shown in Figure 7, in the inner space of the front fitting portion 13FE, the smoothed flat portion 13aE and the smoothed flat portion 13bE face each other. In contrast, various patterns can be adopted for the front portion of the pressing member. For example, on the front portion of the pressing member, the side surface facing the flat portions 13aE and 13bE of the front fitting portion 13FE may be formed into a mountain-shaped surface with two vertices as shown in Figure 4(A). Of course, it is also possible to increase the number of vertices to an appropriate number.

[0079] Furthermore, on the front side of the pressing member, the side surface facing the flat portions 13aE and 13bE of the front fitting portion 13FE can be formed into an arc-shaped surface as shown in Figure 5(A). Alternatively, on the front side of the pressing member, the side surface facing the flat portions 13aE and 13bE of the front fitting portion 13FE can be formed into a dome-shaped spherical surface as shown in Figure 6(A).

[0080] Furthermore, in the embodiments described above and the modified examples shown in Figures 4 to 7, the opposing surfaces at the top and bottom of the figure are arranged in such a way that a flat portion faces a mountain-shaped surface, a flat portion faces an arc-shaped surface, and a flat portion faces a spherical surface. However, this is not the only way. The opposing surfaces at the left and right of the figure may also be arranged in such a way that a flat portion faces a mountain-shaped surface, a flat portion faces an arc-shaped surface, and a flat portion faces a spherical surface. Of course, the opposing surfaces at the top and bottom of the figure and the opposing surfaces at the left and right of the figure may also be formed in the manner described above. The point is that when a rotational force is applied to the core and the pressing member around the axis, the inner wall surface of the holding member and the side surface of the pressing member do not strongly engage, but rather the surfaces engage softly. This prevents the core and the pressing member from rotating around the axis, and also prevents them from moving in the axial direction.

[0081] <Modification 5: Deformation of the rear side of the pressing member> Figure 8 illustrates another example of the pressing member. As can be seen by comparing Figure 8 with Figure 2(B), the pressing member 14B in this example is characterized by the front overhang portion 14xB and the rear overhang portion 14zB of the rear portion 14BB. The other parts are configured in the same way as the pressing member 14 shown in Figure 2(B). For this reason, in Figure 8, parts configured in the same way as the pressing member 14 shown in Figure 2(B) are given the same reference numerals as in the case of the pressing member 14 in Figure 2(B).

[0082] In the case of the pressing member 14B shown in Figure 8, protrusions xT1, xT2, xT3, and xT4 are provided on the side surface of the front overhang portion 14xB. In Figure 8, protrusions xT3 and xT4 are not visible, but protrusion xT3 is located opposite protrusion xT1, straddling the core body holding hole 14L. Protrusion xT4 is located opposite protrusion xT2, straddling the core body holding hole 14L. In other words, there is one protrusion each on the top, bottom, left, and right sides of the side surface of the front overhang portion 14xB.

[0083] Similarly, in the case of the pressing member 14B shown in Figure 8, protrusions zT1, zT2, zT3, and zT4 are provided on the side surface of the rear overhang portion 14zB. In Figure 8, protrusions zT3 and zT4 are not visible, but protrusion zT3 is located opposite protrusion zT1, straddling the core body holding hole 14L. Protrusion zT4 is located opposite protrusion zT2, straddling the core body holding hole 14L. In other words, there is one protrusion each on the top, bottom, left, and right sides of the side surface of the front overhang portion 14xB.

[0084] This reduces the contact area between the side surfaces of the front protrusion 14xB and the rear protrusion 14zB of the rear portion 14BB and the inner wall surface of the rear fitting portion 13Bk of the holding member 13. In other words, it reliably prevents the side surfaces of the front protrusion 14xB and the rear protrusion 14zB of the rear portion 14BB from strongly engaging with the inner wall surface of the rear fitting portion 13Bk of the holding member 13. This allows for smoother movement of the core body 24 and the pressing member 14B in response to writing pressure in the axial direction.

[0085] The number of protrusions, the size of the protrusions, and the position of the protrusions on the sides of the front overhang 14xB and the rear overhang 14zB can be varied. In the case of the pressing member 14B shown in Figure 8, it is also possible to provide protrusions on the arc-shaped side of the front part 14F.

[0086] <Other examples of the shape of the holding member and pressing member, etc.> In the embodiment described above, the retaining member 13 Rear end side The pressure detection unit 25X is positioned as shown, but this is not the only configuration. The holding member 13 can also be configured to hold both the pressing member 14 and the pressure detection unit 25X.

[0087] Furthermore, although the core body 24 and the pressing member 14 were described as separate entities in the above-described embodiment, it is also possible to construct a core body portion in which the core body 24 and the pressing member 14 are integrated. Also, in the above-described embodiment, the holding member 13 has a front fitting portion 13F and a rear fitting portion with a longer inner diameter than the front fitting portion 13F. 13Bk It was described as having a cylindrical shape comprising the following. Accordingly, the pressing member 14 has a front part 14F and a rear part that has a longer outer diameter than the front part. 14Bk It was described as a cylindrical shape having the following features. However, it is not limited to this.

[0088] For example, the retaining member may be a cylindrical body with a uniform inner diameter. Accordingly, the corresponding core body can also be a cylindrical shape with a uniform outer diameter in the portion held by the retaining member. In this case, a flat portion parallel to the axial direction is provided on at least a part of the side surface of the core body. On the other hand, a convex portion is provided on a part of the inner wall surface of the retaining member. When the core body is mounted in the housing, the flat portion of the core body and the convex portion of the retaining member should face each other. In this case, the flat portion provided on the core body may be the portion of the core body housed in the retaining member and constitute the core body, or it may be the portion of the core body housed in the retaining member and constitute the pressing member.

[0089] Conversely, a protrusion is provided on at least a portion of the side surface of the core body. On the other hand, a flat portion parallel to the axial direction is provided on a portion of the inner wall surface of the retaining member. When the core body is mounted in the housing, the protrusion of the core body and the flat portion of the retaining member should face each other. In this case, the protrusion provided on the core body may be the portion of the core body that is housed in the retaining member and constitutes the core body, or it may be the portion of the core body that is housed in the retaining member and constitutes the pressing member.

[0090] <Other variations> In the example explained using Figures 3 and 4, the linear vertices Pa, Pb, Pc, Pd, Pe, and Pf, which are extended in the axial direction, do not necessarily have to be provided as continuous linear vertices. The vertices may be formed discontinuously in the axial direction.

[0091] Furthermore, as mentioned above, this invention is applicable to electronic pens configured using an electromagnetic induction method, by providing a resonant circuit composed of a coil and a capacitor connected to the coil. In addition, this invention is also applicable to electronic pens configured using an active capacitive method, by providing a core that transmits power and an oscillator circuit that generates a position indication signal transmitted from the core. [Explanation of Symbols]

[0092] 1, 2...electronic pen, 11...tip holding part, 12...rear end holding part, 13, 13A, 13B, 13C, 13D, 13E...holding member, 13F...front fitting part, 13Bk...rear fitting part, 13L...core insertion hole, 13H ...Rear end opening, 13S...Wide part, 13a, 13b, 13aA, 13bA...Chevron-shaped surface part, Pa, Pb, Pc, Pd, Pe, Pf...Vertex, 13c, 13d, 13cA, 13dA, 13cB, 13cB, 13 cC, 13dC, 13cD, 13dD... arc-shaped inner wall surface, 13aB, 13bB... flat part, Ta, Tb, Tc, Td, Te, Tf, Tg, Th... projection, 13aC, 13bC... arc-shaped surface part, SL... vertex part, 13aD, 13bD... spherical part, SP... vertex part, 13aE, 13bE... flat part, 13cE, 13dE... arc-shaped inner wall surface, 14, 14A, 14B... pressing member, 14F, 14FA... front side part, 14Bk, 1 4BB...rear side, 14x, 14xB...front protrusion, 14y...intermediate part, 14z, 14zB...rear protrusion, 14a, 14b...flat part, 14c, 14d...arc-shaped side, 14aA, 14bA...mountain-shaped surface, 14cA, 14dA...arc-shaped side, PC, PD...linear part (vertex), 14L...core holding hole, xT1, xT2, xT3, xT4...protrusion, zT1, zT2, zT3, zT4...protrusion, 21...coil, 21a, 21b...Extended wire (conductor wire), 22...Ferrite core, 23...Housing, 23a...Opening, 24...Core body, 25...Connection part, 25A...Molded part, 25B...Pressure detection part, A1...Core body holding part, A2...Conductive rubber, A3...Ring spacer, A4...Dielectric, A5...Terminal member, 25C...Matching part, 25D...Connection terminal part, 26...Printed circuit board, 27...Circuit board protection pipe, 28...Pipe cover, 29...Rear end cover, Cf...Capacitor

Claims

1. A cylindrical housing having an opening at one end, A rod-shaped core is mounted inside the housing, with one end protruding from the opening of the housing as a pen tip, A pressure detection unit fixed within the housing detects the pressure applied to the core, A pressing member holds the rear end of the core inserted through the opening of the housing and presses the pressure detection unit in accordance with the pressure applied to the core, A cylindrical holding member fixed inside the housing houses and holds the pressing member. Equipped with, The pressing member is substantially cylindrical in shape and consists of a front portion and a rear portion that has a larger diameter than the front portion. The front end surface of the front portion is provided with a core-holding hole into which the rear end of the core is inserted. The holding member comprises a front fitting portion into which the front portion of the pressing member fits, and a rear fitting portion into which the rear portion of the pressing member fits. The pen tip end of the front fitting portion is provided with an insertion hole into which the core is inserted, and the rear end end of the rear fitting portion is provided with a rear end opening into which the pressing member is inserted. The inner wall surface of the front fitting portion of the retaining member and the side surface of the front portion of the pressing member do not have interlocking grooves or protrusions. The inner edge shape of the front fitting portion of the retaining member and the outer edge shape of the front portion of the pressing member allow the front portion of the pressing member to fit into the front fitting portion of the retaining member. However, rotation of the front portion of the pressing member around its axis is suppressed within the front fitting portion of the retaining member, and the inner wall surface of the front fitting portion of the retaining member and the side surface of the front portion of the pressing member are partially in contact. An electronic pen characterized by the following features.

2. The electronic pen according to claim 1, The front portion of the pressing member is a flat portion of the pressing member, where the sides facing each other across the core-holding hole are flat. The opposing surface of the front fitting portion of the holding member, which faces the flat portion of the pressing member, has a mountain-shaped surface formed by one or more linear portions extending in a direction along the axial direction protruding toward the flat portion of the pressing member, and one or more of these linear portions are capable of contacting the flat portion of the pressing member. An electronic pen characterized by the following features.

3. The electronic pen according to claim 1, The inner wall surface of the front fitting portion of the retaining member is a flat portion of the retaining member where the surfaces facing each other across the front portion of the pressing member are flat. The opposing surface of the front portion of the pressing member, which faces the flat portion of the holding member, is formed into a mountain-shaped surface by having one or more linear portions extending in a direction along the axial direction protruding toward the flat portion of the pressing member, and the one or more of these linear portions are capable of contacting the flat portion of the holding member. An electronic pen characterized by the following features.

4. The electronic pen according to claim 1, The front portion of the pressing member is a flat portion of the pressing member, where the sides facing each other across the core-holding hole are flat. The opposing surface of the front fitting portion of the holding member, which faces the flat portion of the pressing member, is arc-shaped, and the apex of the arc-shaped opposing surface is capable of contacting the flat portion of the pressing member. An electronic pen characterized by the following features.

5. The electronic pen according to claim 1, The inner wall surface of the front fitting portion of the retaining member is a flat portion of the retaining member where the surfaces facing each other across the front portion of the pressing member are flat. The opposing surface of the front portion of the pressing member that faces the flat portion of the holding member is arc-shaped, and the apex of the arc-shaped opposing surface is capable of contacting the flat portion of the holding member. An electronic pen characterized by the following features.

6. The electronic pen according to claim 1, The front portion of the pressing member is a flat portion of the pressing member, where the sides facing each other across the core-holding hole are flat. The opposing surface of the front fitting portion of the holding member, which faces the flat portion of the pressing member, is spherical in shape, and the apex of the spherical opposing surface is capable of contacting the flat portion of the pressing member. An electronic pen characterized by the following features.

7. The electronic pen according to claim 1, The inner wall surface of the front fitting portion of the retaining member is a flat portion of the retaining member where the surfaces facing each other across the front portion of the pressing member are flat. The opposing surface of the front portion of the pressing member that faces the flat portion of the holding member is spherical, and the apex of the spherical opposing surface is capable of contacting the flat portion of the holding member. An electronic pen characterized by the following features.

8. The electronic pen according to claim 1, The rear portion of the pressing member consists of a front overhang, an intermediate portion, and a rear overhang, and the diameter of the intermediate portion is shorter than the diameters of the front overhang and the rear overhang. An electronic pen characterized by the following features.

9. The electronic pen according to claim 1, The rear portion of the pressing member is provided with a plurality of protrusions on its side surface that contact the inner wall surface of the rear fitting portion of the holding member. An electronic pen characterized by the following features.

10. The electronic pen according to claim 1, A resonant circuit is installed, which consists of a coil wound around the side of the core and a capacitor connected to the coil. An electronic pen characterized by the following features.

11. The electronic pen according to claim 1, The core is electrically conductive, The system includes a transmitting circuit that supplies a position indication signal transmitted from the core to the core. An electronic pen characterized by the following features.

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